creating two points (x,y) and adding them together..

[ghoul]

You probably want this to create the points:

def createPoints():
    x1 = int(input ('Enter a value x of point a '))
    y1 = int(input ('Enter a value y of point a '))
    x2 = int(input ('Enter a value x of point b '))
    y2 = int(input ('Enter a value y of point b '))

    return [[x1, y1], [x2, y2]]

To add the points:

def additionAB (points):
    c = points[0][0] + points[1][0], points[0][1] + points[1][1]
    return c

The call them

print(additionAB(createPoints()))